Telegraph-key.



J. P. CAMPBELL. TELEGRAPH KEY.

APPLICATION FILED JAN. 29, 1906 Wihwoom PATENTED JULY 17, 1906. L

U ITED STATES PATENT OFFICE.

JOSEPH PRESTON CAMPBELL, OF PULASKI, VIRGINIA.

TELEGRAPH-KEY.

To ltZZ whom it may concern:

Be it known that I, Josnrn PRESTON CAMPBELL, a citizen of the United States of America, and a resident of Pulaski, county of Pulaski, State of Virginia, have invented certain new andv useful Improvements in Telegraph-Keys, of which the following is a full and clear specification, reference being had. to the accompanying drawings, in which- Figure 1 is a view, partly in section and partly in side elevation, showing my invention applied to'a well-known type of telegraph-key; Fig. 2, a plan view thereof, and Fig. 3 a detail section showing the lower contact mounted on the lower lever.

The main object of my invention is to provide extremely simple means'whereby I obtain, first, a higher speed; second, maximum durability of the contacts; third, highest quality of writing, and, fourth, lightness of touch, as more fully hereinafter set forth.

Other objects appear in the course of this description.

Referring to the drawings by reference characters, A designates the main or key lever, which is pivoted on the trunnions a, as usual, is provided with the usual upper contact I), and is normally held up by spring 0. The lower contact f is supported in the rear end of a supplemental lever B, pivoted at (Z directly under the key-lever, the axis of this pivot being approximately parallel with the axis of the pivots c of the key-lever.

The forward shorter arm of the lever B is reduced and rounded at e and extended loosely through the downwardly-curved. forward end of the key-lever, thus forming a pivotal or hinge connection with the key-lever. The lower contact is a considerable distance farther from pivot (Z than the hinge connection to the key-lever. The lower contact is insulatingly supported in a block 9 of insulation and is connected by a flexible insulated wire it to the usual spring contactplate i of the switch. The usual connections are made whereby the contacts are made the terminals of the circuit.

Upon-depressing the key the contacts will Specification of Letters Patent.

Application filed January 29, 1906.

Patented July 17, 1906.

Serial No. 298,490.

when so adjusted the trouble known as sticking is very apt to manifest itself, especially when working on a heavy current, this trouble being due to the formation of an arc between the contacts during the rapid making and breaking of the circuit. This are completes the circuit, and therefore renders sending impossible, and in the ordinary key this can only be avoided by making a' wide adjustment of the contacts, which is seriously objectionable, because it necessitates a greater movement of the arm of the operator, and therefore results in a material reduction in speed. This trouble is entirely avoided in my invention, as I provide for a very wide separation of thecontacts without necessitating either an increased movement of the key-lever or the exertion of an appre ciably greater force to depress the key-lever, thereby permitting a maximum speed to be maintained, even on the strongest circuits, with an extremely gentle touch. It will be observed that While in the ordinary keys the movement of the finger end of the key-lever is much greater in all adjustments than the normal distance between the contacts in my device the contrary is the fact, the separation of the contacts being greater than the movement of the lever, as should be the case to secureideal conditions of operation. Thus augmenting the separation of the contacts within a given time obviously secures another very desirable result. It insures a sharper make and break, and thus improves the quality of the sending by making it more decisive and distinct. Thus mounting both contacts on lever members both of which are movably supported the contents are, so to speak, suspended in the air, the result of which is that the instrument is rendered practically noiseless and the life of the contacts greatly prolonged.

It will be apparent to those skilled in the art that various mechanical embodiments of the invention are possible, and I therefore do not wish to be limited to the exact arrangement and construction shown. I

NVhat I claim, and desire to secure by Letters Patent, is

1. In a telegraph instrument, a movable key-lever carrying one of the contacts, an auxiliary lever carrying the other contact and connecting means whereby the operation of the key-lever will simultaneously actuate the contacts.

2. In a telegraph instrument, a key-lever carrying one of the contacts, a movable member carrying the other contact and connections whereby the operation of the key-lever moves both contacts. a

3. In a telegra h instrument, a key-lever, a pair of movab e contacts one of which is carried by the key-lever, and means whereby the contacts are simultaneously brought together or separated by the key-lever.

e. In a telegrah instrument, an actuating-lever, a pair 0 1 contacts both of which are anovable, and auxiliary means for simultaneously separating or brmgmg together the 5 contacts by the movement of the lever.

5. In a telegraph instrument, a key-lever carrying a contact, and an auxiliary lever pivotally mounted and having its shorter JOSEPH PRESTON CAMPBELL,

Witnesses:

W. B. ODDIE, F. B. WILSON. 

